Improved rock-drill



UNITED STATES PATENT OFFICE.

JOHN GREIYES, OF BROOKLYN, NEW YORK.

IMPROVED ROCK-DRILL.

To all 'whom 'it may concern:

Be it known that I, JOHN GREIVES, of the city of Brooklyn, in the county of Kings and State ot' New York, have invented a new and useful Improvement in Rock-Drills; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, inaking a part of this specification, in which- Figure 1 is a vertical elevation. Fig. 2 is a transverse section taken in the line x .ac ot' Fig. 1. Fig. 3 is a plan view ot the lower end of the drill.

Similar letters of reference indicate similar parts in all the igures.

This invention relates to that class of drills which are employed for boring Artesian wells and for drilling rocks and similar substances; and it consists in a novel construction of such a drill, whereby, though it is made more effective in its operation than the drills'in common use, it can be manufactured by any blacksmith ot' ordinary skill without special tools, and greater facility is afforded for its sharpening and repair.

To enable those skilled in the art to understand the nature and operation ot' my invention, I will proceed to describe it with reference to the drawings.

A represents the drill-rod, which may be either solid or tubular, and the lower end of which is made square or rectangular in its cross-section, and terminates in a chisel-like edge, a, which forms the central cutter of the drill. Placed longitudinally upon each of the liat sides of the square lower end ofthe drillrod, and securely fastened thereto by bolts m n, is a section, Z), made of steel-plate, the lower end of which is made sharp to form the edges ot the cutters, of which there are three on each section, the sides or lateral edges c of the section being turned out at right angles to the central part, which iits against the hat side ot' the drill-rod, the lower end or edge of the said central part forming one cutter, and the lower edge of the sides c, which are turned out at right angles to the central portion of the section, as just described, constituting the other two. One of these sections b being secured to each of the four flat sides of the lower end of the drill-rod, the cutters formed by the central portions ofthe said sections surround the central cutter, a, upon the extremity of the drillrod, while the cutters formed by the adjacent sides c of two sections project outward from the corners thereof at right angles to each other,

as clearly shown in Figs. 2 and 3. The central cutter, a, projects downward some little distance below the other cutters. The sides c are narrower at the top than at the bottom, but

are made thicker in order to secure uniform strength throughout the sam e, theproper shape being given by simply upsetting the metal, which, in reducing its width, makes it proportionally thicker. A

In order to prevent the bolts m from being broken or injured by the percussive action upon the sections of each stroke of the drill, a collar, u, is placed upon the drill-rod A above the sect-ions and forced irml y down upon them in such a way as to brace them against the percussion ot1 the blow or stroke, and thus prevent excessive strain upon the bolts m, the collar u being secured to the drill-rod by a nut fitted to a screw-thread on the rod a, or by any suitable means. This collar u is only necessary when a solid drill-rod is used, its place being supplied when a hollow drill-rod is employed by the ordinary iiange or collar ot' such hollow rod.

The drill is operated by the same means and in the same manner as other rock-drills, its cutting-edges, formed as just described, abrading and penetrating the rock to be drilled in the same manner. When it is desired that a greater extent of cutting-edges be caused to act upon the rock or stone, as in drilling through very hard rock, a solid steel block may be itted into each section b, resting upon lits central portion between its sides c, and held in place by the same bolts that confine the sec tion to the drillrod. rEhe lower ends ot' these additional steel blocks are made with diamondshaped points, which assist the action of the cutters t'orined upon the drill itself.

By forming the cutters in the manner described they may be readily removed from the drill-rod to be sharpened or repaired, which operation, as well as the construction of the cutters in the tirst place, may be performed by a blacksmith or other comparatively unskilled worker in wrought-iron.

What I claim as new, and desire to secure by Letters Patent, is-

lhe drill constructed of a central polygonal rod with cutting-point and angular sectional cutters bolted to the sides of said rod, substantially as herein specified.

JOHN GREIVES.

Witnesses:

A. LE CLERC,

J. W. GooMBs. 

